Saint-Petersburg is the world’s first megalopolis to stop the use of liquid chlorine for potable water disinfection


The official ceremony of discarding the last chlorine container was held at the Northern Waterworks on 26 June, 2009. All city waterworks have changed over from chlorine to sodium hypochlorite – a chemical no less effective but non-hazardous during transportation and storage.

Chairman of the State Duma B.V. Gryzlov, Deputy Chairman of the Federation Council S.Y. Orlova, Governor of Saint-Petersburg V.I. Matveenko and Chairman of the Legislative Assembly of Saint-Petersburg V.A. Tulpanov took part in the ceremony.

The use of chlorine for water disinfection began in Saint-Petersburg 100 years ago – in 1909. Chlorine ensured epidemiological safety of drinking water but led to some problems as it is an aggressive poisonous substance.

In 2003, SUE “Vodokanal of St. Petersburg” used for the first time sodium hypochlorite as an alternative to liquid chlorine in the disinfection process.

In 2003-2004, all suburban waterworks, the Main and Volkhovskaya Waterworks changed over to sodium hypochlorite.

In 2006, production of low-concentrated sodium hypochlorite solutions from table salt was launched at the biggest WTP - Southern Waterworks.

In 2008, a similar production plant was built at the Northern Waterworks.

See the Press Release dedicated to elimination of the last chlorine container.